Advanced Visual Field Defects Research Articles

Awareness for glaucoma in the general population

Glaucoma is not arare entity but because very few symptoms occur and visual field defects are frequently first recognized at a late stage, alarge proportion of glaucoma diseases remain undetected. The aim of this study was to identify the proportion of undiagnosed glaucoma in German population-based cohort studies and to contextualize them in the context of the literature. The prevalence of glaucoma in the Gutenberg Health Study (GHS) and the age-related investigations on health of the University of Regensburg (AugUR) was evaluated based on visual field examinations and optic disc color photography according to the ISGEO criteria. Furthermore, the self-reported glaucoma diagnoses were collected and the proportion of undiagnosed glaucoma was determined. The proportion of undiagnosed glaucoma was 55% in the GHS, and 53% in the AugUR study. The results correlate with results from previous studies from other countries in which the proportion of unrecognized glaucoma ranged from 33% to 78%. In the GHS and the AugUR study the proportion of undiagnosed glaucoma was higher in younger age groups and in women. Roughly every second case of glaucoma is undetected. As the symptoms are often nonspecific or take a long time to appear, there is arisk of advanced glaucomatous visual field defects or blindness due to a lack of glaucoma awareness. Studies have shown that asystematic screening can halve this risk.

Suprathreshold Approaches to Mapping the Visual Field in Advanced Glaucoma.

Measuring the spatial extent of defects may be advantageous in advanced glaucoma where conventional perimetric sensitivity measurements are unreliable. We test whether suprathreshold tests on a higher density grid can more efficiently map advanced visual field loss. Data from 97 patients with mean deviation < -10 dB were used in simulations comparing two suprathreshold procedures (on a high-density 1.5° grid) to interpolated Full Threshold 24-2. Spatial binary search (SpaBS) presented 20-dB stimuli at locations bisecting seen/unseen points until the seen status of all neighbors matched or until tested points were adjacent. The SupraThreshold Adaptive Mapping Procedure (STAMP) presented 20-dB stimuli where entropy was maximal and modified the status of all points after each presentation, stopping after a fixed number of presentations (estimated as 50%-100% of the presentation number of a current procedure). With typical response errors, SpaBS had worse mean accuracy and repeatability than Full Threshold (both P < 0.0001). Compared to Full Threshold, mean accuracy (Full Threshold: median, 91%; interquartile range [IQR], 87%-94%) was slightly better with STAMP for all stopping criteria, although this was not statistically significant until 100% of conventional test presentations were used. Mean repeatability for STAMP was similar for all stopping criteria (P ≥ 0.02) compared to Full Threshold (Full Threshold: median, 89%; IQR, 82%-93%). STAMP accurately and repeatably maps the spatial extent of advanced visual field defects in as few as 50% of conventional perimetric test presentations. Further work is needed to test STAMP in human observers and in progressive loss. New perimetric approaches may improve information available for advanced glaucoma management and may potentially be more acceptable to patients.

Patterns of Visual Field Loss in Early, Moderate, and Severe Stages of Open Angle Glaucoma.

Even in the early stages of glaucomatous visual field defects (VFDs), 49% of the defects occurred in both hemifields and 28% involved the central 5 degrees of the visual field (VF), which may have prognostic values. The aim was to determine the patterns of glaucomatous VFDs in early, moderate and severe stages of primary open angle glaucoma, using the Glaucoma Staging Application. According to the Modified University of Sao Paulo Glaucoma Visual Field Staging System Classification, patients with early, moderate and advanced VFDs were selected by the Glaucoma Staging Application using all databases of the Humphrey Visual Field Analyser of a glaucoma referral practice. We analyzed one VF of the 100 patients included in each group. The analysis consisted of classifying all exams regarding the location of the defects, the hemifields involved, and the connection to the blind spot. We analyzed 300 VF. In the Early group, 27% of the VFDs are connected to the physiological blind spot, 64% in the Moderate group, and 95% in the Severe group ( P <0.01). In the Early group, 28% of the defects involved the central 5 degrees of the fixation, 59% in the Moderate and 88% in the Severe group. In the Early group, 49% of the defects involved both hemifields, 80% in the Moderate and 80% in the Severe group. With increasing glaucoma severity, VFD showed a more central pattern, connected to the blind spot, and involved both hemifields. In early disease, both hemifields were commonly affected and more than a quarter of VFD involved the central 5 degrees close to fixation. Careful monitoring of the central VF in glaucoma is suggested.

Bilateral Cataract Development and Pupillary Block Glaucoma Following Implantable Collamer Lens.

Aim and objectiveWe report the first case of bilateral cataract formation and pupillary block glaucoma and high intraocular pressure (IOP) following implantable Collamer lens (ICL) implantation that resulted in advanced visual field loss.BackgroundThe patient who underwent bilateral ICL implantation can develop bilaterally elevated IOP and an anterior subcapsular cataract with altitudinal visual field defect.Case descriptionA 38-year-old man with high myopia presented for routine follow-up status post bilateral phakic ICL placement. The visual acuity was reduced due to an anterior subcapsular cataract and elevated IOP in both eyes with advanced glaucomatous visual field defects. The patient was treated with topical glaucoma medications. The left eye underwent same-day phakic ICL explanation and cataract surgery to prevent further visual field loss.ConclusionCataract and glaucoma are serious complications after phakic ICL implantation; therefore, regular postoperative monitoring may prevent advanced visual impairment.Clinical significanceThe use of a phakic intraocular lens for the correction of myopia may result in complications. As a measure is to reduce such complications, refractive surgeons preferred using phakic posterior chamber intraocular Collamer lens for the correction of myopia.How to cite this articleOwaidhah O, Al-Ghadeer H. Bilateral Cataract Development and Pupillary Block Glaucoma Following Implantable Collamer Lens. J Curr Glaucoma Pract 2021;15(2):91–95.

Diode laser transscleral cyclophotocoagulation causes intraocular collamer lens displacement in pseudophakic eye: a case report

BackgroundWith the rapid development of intraocular collamer lens (ICL) operation, it is foreseeable that we will encounter a large number of glaucoma patients with ICL implantation history. However, our current understanding of the treatment of glaucoma patients with ICL is limited. Hence we report a rare case of refractory glaucoma after intraocular collamer lens and intraocular lens implantation in a patient who underwent unsuccessful transscleral cyclophotocoagulation, which led to intraocular collamer lens displacement, angle closure and uncontrolled intraocular pressure.Case presentationA 39-year-old woman presented with intractably elevated intraocular pressure in the right eye. Since her intraocular collamer lens implantation surgery in 2017, her intraocular pressure had remained over 40 mmHg while using 3 types of anti-glaucoma medications. The patient had a history of phacoemulsification and posterior chamber phakic intraocular lens implantation for complicated cataracts secondary to uveitis in 2006. On gonioscope examination, there were signs of pigment dispersion, and the anterior chamber angle was open. Ultrasound biomicroscopy examination showed contact and rubbing between the intraocular collamer lens and posterior surface of the iris. And typical advanced glaucomatous optic neuropathy and visual field defects were observed. Transscleral cyclophotocoagulation was performed to control the intraocular pressure and prevent further visual field loss. However, the intraocular collamer lens was displaced after transscleral cyclophotocoagulation, which resulted in formation of a shallow anterior chamber 1 week later, angle closure and loss of intraocular pressure control 1 month later, even though the maximum dose of anti-glaucoma medication was used. Finally, an Ahmed glaucoma valve was successfully implanted in her anterior chamber, and the glaucoma was controlled, as observed at the 10-month follow-up.ConclusionsPigment dispersion is a common phenomenon after intraocular collamer lens implantation and may accelerate the progression of glaucoma. Transscleral cyclophotocoagulation should be carefully considered in glaucoma patients with elevated intraocular pressure after intraocular collamer lens implantation, given that transscleral cyclophotocoagulation may cause intraocular collamer lens displacement.

Does hemispheric vascular regulation differ significantly in glaucoma patients with altitudinal visual field asymmetry? A single-center, prospective study

PurposeVascular risk factors and ocular perfusion are heatedly discussed in the pathogenesis of glaucoma. The retinal vessel analyzer (RVA, IMEDOS Systems, Germany) allows noninvasive measurement of retinal vessel regulation. Significant differences especially in the veins between healthy subjects and patients suffering from glaucoma were previously reported. In this pilot-study we investigated if localized vascular regulation is altered in glaucoma patients with altitudinal visual field defect asymmetry.Methods15 eyes of 12 glaucoma patients with advanced altitudinal visual field defect asymmetry were included. The mean defect was calculated for each hemisphere separately (−20.99 ± 10.49 profound hemispheric visual field defect vs −7.36 ± 3.97 dB less profound hemisphere). After pupil dilation, RVA measurements of retinal arteries and veins were conducted using the standard protocol. The superior and inferior retinal vessel reactivity were measured consecutively in each eye.ResultsSignificant differences were recorded in venous vessel constriction after flicker light stimulation and overall amplitude of the reaction (p < 0.04 and p < 0.02 respectively) in-between the hemispheres. Vessel reaction was higher in the hemisphere corresponding to the more advanced visual field defect. Arterial diameters reacted similarly, failing to reach statistical significance.ConclusionLocalized retinal vessel regulation is significantly altered in glaucoma patients with asymmetric altitudinal visual field defects. Veins supplying the hemisphere concordant to a less profound visual field defect show diminished diameter changes. Vascular dysregulation might be particularly important in early glaucoma stages prior to a significant visual field defect.

Depression and Severity of Glaucoma Among Older Adults in Urban and Suburban Areas.

Depression increases with severity of visual field defect in older adults with primary open-angle glaucoma (POAG). This study aimed to determine the prevalence of depression among patients with POAG and examine the relationship between depression and the severity of POAG in older adults. Three hundred and sixty patients with POAG aged 60 years or above were recruited from 2 tertiary centers located in an urban and suburban area. The participants were stratified according to the severity of their glaucoma based on the scores from the modified Advanced Glaucoma Intervention Study (AGIS) to mild, moderate, severe, and end stage. Face-to-face interviews were performed using the Malay Version Geriatric Depression Scale 14 (mGDS-14) questionnaire. Depression is diagnosed when the score is ≥8. One-way analysis of variance was used to compare the subscores between the groups. Multifactorial analysis of variance was also applied with relevant confounding factors. Depression was detected in 16% of older adults with POAG; a higher percentage of depression was seen in those with end stage disease. There was a significant increase in the mean score of mGDS-14 according to the severity of POAG. There was evidence of an association between depression and severity of visual field defect (P<0.001). There was a significant difference in mGDS-14 score between the pairing of severity of POAG [mild-severe (P=0.003), mild-end stage (P<0.001), moderate-severe (P<0.001), and moderate-end stage (P<0.001)] after adjustment to living conditions, systemic disease, and visual acuity. Ophthalmologists should be aware that older adults with advanced visual field defects in POAG may have depression. The detection of depression is important to ensure adherence and persistence to the treatment of glaucoma.

Effects of driver compensatory behaviour on risks of critical pedestrian collisions under simulated visual field defects.

Compensatory behaviour is regarded as a helpful strategy to mediate drivers’ deteriorated hazard perception ability due to visual field defects. However, helpfulness of compensatory behaviour for drivers with advanced visual field defects has largely unexplored. This study aims to clarify the effectiveness and limitation of compensatory head movements in critical situations where included pedestrians stepping off a sidewalk under the simulation of advanced visual defects. 18 healthy-sighted drivers participated the data collection that was conducted in a driving simulator under three driving conditions: (1) without visual impairment, (2) with visual impairment and not performing active compensation, and (3) with visual impairment but performing active compensation. The result showed that active compensation led quick accelerator and brake response times, reducing the risk and number of pedestrian collisions. The active compensation led a decrease in the number of non-responses to hazardous pedestrians compared to while driving not performing compensation. However, the compensation could not reduce the number of pedestrian collisions to those of healthy-sighted drivers. Compensatory viewing behaviour contributed to improved driving performance as well as has limits to lead driving performance like healthy-sighted drivers. Developing driver assistance systems and practical compensatory strategies concerning the degrees of impairment and traffic conditions may provide opportunities to improve driving safety deteriorated hazard perception for visually impaired drivers.

Use of Virtual Reality Simulation to Identify Vision-Related Disability in Patients With Glaucoma

Clinical assessment of vision-related disability is hampered by the lack of instruments to assess visual performance in real-world situations. Interactive virtual reality (VR) environments displayed in a binocular stereoscopic VR headset have been designed, presumably simulating day-to-day activities to evaluate vision-related disability. To investigate the application of VR to identify vision-related disability in patients with glaucoma. In a cross-sectional study, 98 patients with glaucoma and 50 healthy individuals were consecutively recruited from a university eye clinic; all participants were Chinese. The study was conducted between August 30, 2016, and July 31, 2017; data analysis was performed from December 1, 2017, to October 30, 2018. Measurements of visual acuity, contrast sensitivity, visual field (VF), National Eye Institute 25-item Visual Function Questionnaire Rasch score, and VR disability scores determined from 5 VR simulations: supermarket shopping, stair and city navigations in daytime, and stair and city navigations in nighttime. Duration required to complete the simulation, number of items incorrectly identified, and number of collisions were measured to compute task-specific and overall VR disability scores. Vision-related disability was identified when the VR disability score was outside the normal age-adjusted 95% confidence region. Virtual reality disability score. In the 98 patients with glaucoma, mean (SD) age was 49.8 (11.6) years and 60 were men (61.2%); in the 50 healthy individuals, mean (SD) age was 48.3 (14.8) years and 16 were men (32.0%). The patients with glaucoma had different degrees of VF loss (122 eyes [62.2%] had moderate or advanced VF defects). The time required to complete the activities by patients with glaucoma vs healthy individuals was longer by 15.2 seconds (95% CI, 5.5-24.9 seconds) or 34.1% (95% CI, 12.4%-55.7%) for the shopping simulation, 72.8 seconds (95% CI, 23.0-122.6 seconds) or 33.8% (95% CI, 10.7%-56.9%) for the nighttime stair navigation, and 38.1 seconds (95% CI, 10.9-65.2 seconds) or 30.8% (95% CI, 8.8%-52.8%) for the nighttime city navigation. The mean (SD) duration was not significantly different between the glaucoma and healthy groups in daytime stair (203.7 [93.7] vs 192.9 [89.1] seconds, P = .52) and city (118.7 [41.5] vs 117.0 [52.3] seconds, P = .85) navigation. For each decibel decrease in binocular VF sensitivity, the risk of collision increased by 15% in nighttime stair (hazard ratio [HR], 1.15; 95% CI, 1.08-1.22) and city (HR, 1.15; 95% CI, 1.08-1.23) navigations. Fifty-eight patients (59.1%) with glaucoma had vision-related disability in at least 1 simulated daily task; a higher proportion of patients had vision-related disability in nighttime city (27 of 88 [30.7%]) and stair (27 of 90 [30.0%]) navigation than in daytime city (7 of 88 [8.0%]) and stair (19 of 96 [19.8%]) navigation. The overall VR disability score was associated with the National Eye Institute 25-item Visual Function Questionnaire Rasch score (R2 = 0.207). These findings suggest that vision-related disability is associated with lighting condition and task in patients with glaucoma. Virtual reality may allow eye care professionals to understand the patients' perspectives on how visual impairment imparts disability in daily living and provide a new paradigm to augment the assessment of vision-related disability.

Clinical Characteristics of Patients Newly Diagnosed with Primary Open Angle Glaucoma at the Yaoundé Central Hospital-Cameroon

Objective: To describe the clinical characteristics of patients newly diagnosed with primary open angle glaucoma (POAG) in a tertiary hospital. Methods: A review of the medical records of patients newly diagnosed with POAG between 1st January 2016 and 31st January 2018 was done. POAG diagnosis was based on the presence of any two of the following: elevated intraocular pressure (IOP), glaucomatous optic nerve changes and characteristic visual field defects in the presence of a normal angle on gonioscopy. Blindness was defined as corrected distant visual acuity (CDVA) of 0.05. Results: Amongst the 10 400 new patients seen during the study period, 96 were diagnosed with POAG (0.92%). The male: female sex ratio was 1.5. The mean age was 49.1 ± 19.9 years. Family history of glaucoma was present in 11 patients (11.46%). The mean cup/disc ratio was 0.6 ± 0.2. Glaucomarelated blindness was unilateral in 5.2% of patients (n=5). No patient had bilateral blindness. Unilateral J Ophthalmol Res 2019; 2 (3): 050-056 DOI: 10.26502/fjor.2644-00240011 Journal of Ophthalmology and Research 2 and bilateral severe visual impairment were present respectively in 10.42% and 33.33% of cases. Conclusion: Late presentation is common in POAG with severe cupping and moderate to advanced visual field defects. Unilateral blindness or severe visual impairment is present in 38.5% of cases. Information and screening should be put in place to encourage early diagnosis which will reduce the burden of glaucoma-related blindness.

A study for the assessment of central corneal thickness and visual field defects in patients of primary open-angle glaucoma

Purpose: The aim of this study is to assess the central corneal thickness (CCT) and visual field (VF) changes in patients of primary open-angle glaucoma (POAG) and the influence of CCT on glaucomatous damage in glaucoma clinic of Dr. R. P. G. M. C Kangra at Tanda. Materials and Methods: This cross-sectional study conducted on 103 eyes of 58 patients of POAG- >40 years. All patients underwent a complete eye examination including Goldmann applanation tonometry, CCT measurement through ultrasonic pachymeter, stereoscopic disc photography, retinal nerve fiber layer (RNFL) photography, and automated perimetry. Correlation of CCT with age, gender, intraocular pressure (IOP), advanced glaucoma intervention study (AGIS) score, VF parameters (mean deviation, pattern standard deviation [PSD]), vertical cup-disc ratio, average RNFL, and number of antiglaucoma medications was analyzed. The patients were divided into two groups – thin and thick CCT taking a reference range of 529 μm derived from a previous study done in same area with larger sample size. Pearson correlation was used for correlation coefficient and a value of P < 0.05 was considered statistically significant. Results: Thin CCT was significantly correlated with IOP (r = 0.28, P = 0.004). Thin CCT was also significantly associated with worsened PSD of VF (r = 0.25, P = 0.02). The mean AGIS score was more (8.07 ± 5.52) in patients with thin CCT (<529 μm) in comparison (5.96 ± 6.10) to patients with thick CCT (>529 μm) which was statistically significant (P < 0.05). Conclusion: CCT is a significant risk factor for glaucomatous VF loss. Patients with thinner CCT are more likely to have advanced VF defects in comparison to patients with thick CCT.

A Comparative Analysis of the Fear of Falling Between Glaucoma and Age-Related Macular Degeneration Patients From a Developing Country.

PurposeFalls are very prevalent in the older population. Visually impaired elderly patients are prone to falls as the result of visual loss and ageing. The purpose of the study was to compare the fear of falling (FoF) between primary open angle glaucoma (POAG) and age-related macular degeneration (ARMD) patients who live in a developing country.MethodsThis was a cross-sectional observational study. After a complete eye examination including measurement of best-corrected visual acuity, ophthalmoscopy, and automated visual field, all subjects completed the Fall Efficacy Scale International Brazil (FES-I-Brazil) questionnaire.ResultsThe sample comprised 64 patients with POAG, 48 with ARMD, and 52 controls. All groups were matched for age, sex, comorbidity, and ethnic distribution. The FES-I score was 24.6 ± 8.7, 25.3 ± 6.3, and 24.2 ± 7.7 for glaucoma, ARMD, and controls, respectively (P = 0.894). A post hoc analysis comparing all subjects with advanced visual field defect (mean deviation [MD] < −12 dB) revealed a higher FES-I score in ARMD patients as compared to POAG ones (46.2 ± 16.8 and 24.0 ± 7.7 for ARMD and POAG, respectively, P < 0.001).ConclusionIn this cohort of elderly subjects with eye diseases, the FoF was similar among groups; however, ARMD patients with more compromised visual field had higher FoF as compared to POAG patients and controls.Translational RelevanceA high rate of fear of falling exists in ARMD patients with compromised visual field. This finding may be useful in developing multidimensional strategies to decrease fear of falling and improve quality of life in older persons living in a developing country.

Diffusion tensor imaging of the optic disc in idiopathic intracranial hypertension.

To study optic disc in idiopathic intracranial hypertension (IIH) with diffusion tensor imaging. Prospective study was carried out on 31 consecutive patients with IIH and 17 age and sex-matched controls that underwent diffusion tensor imaging of optic nerve. Fractional anisotropy (FA) and mean diffusivity (MD) of optic disc were measured by two readers. Grades of papilledema and visual field defects were evaluated by ophthalmologist. FA of optic disc was significantly lower in IIH than controls (p = 0.001) with excellent inter-observer agreement (K = 0.93) of both readers. The cutoff FA used to differentiating IIH from controls were 0.28 and 0.29 with area under curve (AUC) of 0.921 and 0.914, accuracy 92% and 91%, and sensitivity 97% and 96%. MD of optic disc were significantly higher in IIH than in controls (p = 0.001) with excellent inter-observer agreement (K = 0.91) of both readers. The cutoff MD used to differentiating IIH from controls was 1.51 and 1.22 × 10-3mm2/s with AUC 0.943 and 0.922, and accuracy 94% and 92% respectively. FA of optic disc was significantly lower in early than advanced papilledema and visual field defects (p = 0.001, 0.001) respectively. The MD of optic disc was significantly higher in early than advanced papilledema and visual field defects (p = 0.001, 0.001) respectively. Diffusion tensor imaging parameters of optic disc are non-invasive reliable imaging parameters that can be used for diagnosis of IIH and well correlated with papilledema and visual field defects.

The effect of trabeculectomy surgery on the central visual field in patients with glaucoma using microperimetry and optical coherence tomography.

To determine the functional and structural effects of trabeculectomy surgery on patients with advanced glaucoma and central visual field defects in the early post-operative period. Thirty consecutive adult subjects with advanced glaucoma requiring trabeculectomy surgery and an established visual field defect within 10° of fixation underwent microperimetry (MAIA MP-1, CenterVue, Padova, Italy) and optic disc optical coherence tomography (OCT) imaging (Spectralis, Heidelberg Engineering, Germany) pre-operatively, and 1 month and 3 months following trabeculectomy surgery. Main outcome measures were post-trabeculectomy change in mean threshold on microperimetry and nerve fibre layer thickness on OCT. Fellow eyes were used as controls. The mean change in MP average threshold values from pre-operative to post-operative was 0.6 ± 1.9 dB for treated eyes and 0.1 ± 1.3 dB for control eyes (p = 0.14) at 1 month and 0.2 ± 2.3 and -0.3 ± 1.6 dB at 3 months (p = 0.22). Mean change in global nerve fibre layer thickness was -0.6 and -0.5 µm for operated and control eyes, respectively (p = 0.83), at 1 month and 0.8 and -0.4 µm at 3 months (p = 0.88). The kappa agreement for structure-function correlation between OCT and MP was 0.735 (confidence interval 0.59-0.88) (p < 0.005). Central visual function and retinal nerve fibre layer thickness appear to be preserved in glaucoma patients with central visual field defects undergoing trabeculectomy surgery in the early post-operative period. These data may inform glaucoma surgeons considering trabeculectomy surgery in this patient group.

Advanced pigment dispersion glaucoma secondary to phakic intraocular collamer lens implant

PurposeWe report a case of pigment dispersion glaucoma secondary to uncomplicated phakic intraocular collamer lens (ICL) (Visian ICL™, Staar Inc., Monrovia, CA) implant that resulted in advanced visual field loss. ObservationsA 50-year-old man presented for routine follow-up status post bilateral phakic intraocular collamer lens (ICL) placement 8 years earlier. He was incidentally found to have a decline in visual acuity from an anterior subcapsular cataract and elevated intraocular pressure (IOP) in the left eye. There were signs of pigment dispersion and no evidence of angle closure. Diffuse optic nerve thinning was consistent with advanced glaucomatous visual field defects. Pigment dispersion was also present in the patient's right eye, but without elevated IOP or visual field defects. The patient was treated with topical glaucoma medications and the phakic ICL in the left eye was removed concurrently with cataract surgery to prevent further visual field loss. Conclusions and importancePigment dispersion glaucoma is a serious adverse outcome after phakic ICL implantation and regular post-operative monitoring may prevent advanced visual field loss.

Do We Perform Glaucoma Surgery too Late?

As glaucoma specialists, we often ask ourselves why patients are referred so late for surgery. Usually the patient is referred in a far advanced stage of the disease after long-term conventional treatment with topical medications. By that time, substantial morphologic damage is present and the patient is disabled by far advanced visual field defects. In addition, decompensated intraocular pressure, despite maximal tolerated medical treatment, is seen. Delayed surgery due to late diagnosis is rather a rare event. Various reasons may be responsible for this late referral. Improved IOP-lowering medications (i.e., fixed combinations), personal aversion (fear and knowledge of lack of improvement in visual acuity) against surgery, and imperfect glaucoma procedures may play an important role. A retrospective review of the last 274 cases referred for filtering glaucoma surgery is used to describe and analyze criteria for adequate timing of glaucoma surgery. This study reveals that almost ¾ of patients are referred rather late for glaucoma surgery. Criteria for adequate timing of glaucoma surgery are given for non-glaucoma specialists in particular. They apply for all types of glaucoma surgery, and the pros and cons are discussed in detail. Trabeculectomy is still regarded as the gold standard of glaucoma surgery. Because trabeculectomy may not be an ideal glaucoma procedure, there is hope that the modern less-invasive glaucoma procedures (MIGS) will be able to extend indications for glaucoma surgery. This may also lower the hurdle of referral for glaucoma surgery for both patients and non-glaucoma specialist doctors.

Atopic Glaucoma: Clinical and Pathophysiological Analysis.

Open-angle glaucoma associated with severe atopic dermatitis (atopic glaucoma) tends to be severe and difficult to treat because of ocular surface/eye lid inflammation. To determine the validity of regarding atopic glaucoma as a clinical entity, we carried out retrospective analysis and pathologic investigations. Forty-five cases (62 eyes) of atopic glaucoma were reviewed retrospectively. During surgical treatment, aqueous humor and trabeculectomy specimens were obtained. The aqueous humor samples were analyzed by multiplex cytokine assay. The surgical specimens were analyzed histologically. Atopic glaucoma was often associated with atopic cataracts (43 eyes) and retinal detachments (19 eyes). A history of glucocorticoid medications was absent in 12 cases. A total of 50 eyes required surgical interventions because of advanced visual field defects and/or high intraocular pressures. Bleb-associated postsurgical infections were observed in 7 eyes. Elevated levels of inflammatory cytokines (IL-8 and CCL2) were observed in the aqueous humor samples obtained from atopic glaucoma patients compared with those from senile cataract patients. Ultrastructural analysis of trabecular meshwork tissues obtained from atopic glaucoma patients showed abnormal accumulation of 10 to 30 nm fibers in the corneoscleral meshwork. We would like to propose atopic glaucoma as a new clinical entity, ranging from pure atopic glaucoma to a mixed type of atopic/steroid-induced glaucoma that should be considered as one of the clinical features of atopic ocular complications.

Why Do People (Still) Go Blind from Glaucoma?

Glaucoma is a progressive optic neuropathy and is the leading cause of irreversible blindness worldwide. Over 60 million people were estimated to be affected with open-angle glaucoma (OAG) in 2010, and bilateral blindness from the disease was estimated to be present in 4.5 million people with OAG in 2010, rising to 5.9 million people in 2020.1 In 1982, Grant and Burke2 published an article with a title similar to the present article suggesting three potential reasons why people go blind from glaucoma: one-third were undiagnosed; one-third had not been treated properly; and one-third were noncompliant with therapy. They also noted that, when abnormalities ranging from early glaucomatous cupping to advanced visual field defects were present at initial evaluation, progressive visual field loss continued to occur even with lowered intraocular pressure (IOP). In the consensus of Medical Treatment of Glaucoma by the World Glaucoma Association, the definition of target IOP includes the need to adjust therapy based on numerous factors, among them the initial level of damage, rate of progression, and life expectancy.3 It appears that eyes with more severe damage at presentation require lower IOP to prevent further functional loss or blindness. Forchheimer et al.4 investigated the relationship between baseline visual field damage, IOP, and rate of progression and found that among eyes with more severe functional damage (mean deviation [MD] worse than −12 dB), those with mean follow-up IOP < 14 mmHg progressed more slowly than those with higher pressures. Kotecha et al.5 found that following trabeculectomy, eyes showing changes in both optic nerve and visual field sensitivity had less IOP reduction from baseline compared with eyes showing no progression. Lee et al.6 reported that patients with more severe glaucomatous damage, as measured by both visual field and optic disc cupping, are at highest risk for rapid worsening of the disease and that more aggressive treatment of such patients should be considered to prevent visual disability. Heijl et al.7 showed that treatment is more effective in patients with MD better than −4.5 dB compared to patients with MD worse than −4.5 dB. Thirty years later, despite meaningful improvements in technology, therapeutic tools, and knowledge of the disease, patients continue to go blind from glaucoma. In a retrospective chart review by Peters et al.8 in Sweden, at the time of the last visit 42.2% and 16.4% of patients had at least one eye blind or bilateral blindness from glaucoma, respectively. Overall, the cumulative incidences of blindness in at least one eye and bilateral blindness from glaucoma were 26.5% and 5.5%, respectively, after 10 years, and 38.1% and 13.5% at 20 years.8 A recent report of the population-based study of all residents of Olmsted County, Minnesota,9 showed that the 20-year probability and the population incidence of blindness due to OAG in at least one eye decreased over the 45 years from 1965 to 2009. They also suggested that “… a subset of patients with glaucoma may have more aggressive disease and may be particularly susceptible to progression, possibly because of non-IOP-related factors that contribute to retinal ganglion cell (RGC) death and vision loss.”4 Although there is compelling evidence that “non-IOP-related factors” may indeed have a significant role in glaucoma pathogenesis,10–12 IOP is the major component associated with fast progression rate.13 In a recent review on the pathophysiology of glaucoma, Weinreb et al.14 stated that although the loss of ganglion cells is related to the level of IOP, other factors may also play a role. To date, there is no high-level evidence that non-IOP lowering medications can alter the progression of glaucoma. Yet, it is possible that other treatments may be needed to supplement IOP lowering or to make a given amount of IOP lowering more effective. Our working hypothesis is that even after 30 years of substantial advances in the field, the challenges faced by patients and eye care providers to prevent blindness due to glaucoma have not changed as substantially.

Temporal Retinal Thickness in Eyes With Glaucomatous Visual Field Defects Using Optical Coherence Tomography

To evaluate the temporal macular retinal thickness in normal, early, and advanced glaucomatous eyes using optical coherence tomography 3 (OCT-3) and correlate the superior-to-inferior retinal thickness (S/I RT) ratio with corresponding field defects in early and advanced glaucoma patients. Forty normal eyes, 40 eyes with early glaucomatous visual field defects, and 33 eyes with advanced visual field defects were included. All participants underwent complete ocular and visual field examinations and OCT-3 imaging on the same day. A 3×3 mm area temporal to the foveal reflex was scanned with the OCT-3 using 6 horizontal, equally spaced raster lines. Retinal thickness was evaluated at points 500 μm apart for each line and S/I RT ratio computed between similar points above and below the fovea for each patient. One-way ANOVA was used to compare S/I RT ratio between the normal, early, and advanced glaucoma eyes. Average retinal thickness increased progressively, as points temporal to the fovea were scanned. There was a statistically significant difference between the average superior and inferior retinal thickness at points 1500, 2000, and 2500 μm temporal to the fovea in both early and advanced glaucoma eyes (P<0.05) with corresponding significant differences in the S/I RT ratios, when compared with the normal participants (P<0.017). OCT-3-generated S/I RT ratios were successfully able to reproduce the structural damage in eyes with early and advanced glaucoma field defects and can complement optic disc scanning protocols in diagnosing glaucoma at an early stage.

A Randomized Clinical Trial of Selective Laser Trabeculoplasty Versus Argon Laser Trabeculoplasty in Patients With Pseudoexfoliation

To evaluate the efficacy of selective laser trabeculoplasty (SLT) versus argon laser trabeculoplasty (ALT) in lowering the intraocular pressure (IOP) in patients with open-angle glaucoma or ocular hypertension secondary to pseudoexfoliation. Multicentered randomized clinical trial. A total of 76 eyes from 60 patients with pseudoexfoliation and uncontrolled IOP were recruited from 5 Canadian academic institutions. Patients with prior laser trabeculoplasty, ocular surgery within 6 months, previous glaucoma surgery, an advanced visual field defect, current steroid use, and monocular patients were excluded. Eyes were randomized to receive either 180-degree SLT or 180-degree ALT by a nonblocked randomization schedule stratified by center. The primary outcome was the change in IOP at 6 months versus baseline and secondary outcomes included change in number of glaucoma medications after laser. Baseline variables included age, sex, angle grade, angle pigmentation, and number of glaucoma medications. Of the 76 eyes, 45 eyes received SLT and 31 eyes received ALT. The overall age was 72.9 years (65% females). The baseline IOPs in the SLT and ALT groups were 23.1 and 25.2 mm Hg, respectively (P=0.03). The IOP reduction 6 months after SLT was -6.8 mm Hg and post-ALT was -7.7 mm Hg (P>0.05). The SLT group had reduced glaucoma medications by 0.16 medications at 6 months and the ALT group had no decrease in medications over the same time period (P=0.59). There were no postlaser IOP spikes in either group. ALT and SLT are equivalent in lowering IOP at 6 months posttreatment in patients with PXF.